Artificial wool and art of making same



5 not'found in wool.

Patented Nov. 29, 1932 UNITED STATES GINO M. ROSSATI, OF NEW YORK, Y.

ARTIFICIAL WOOL AND ART OF MAKING SAME No Drawing. Application filed October 6, 1931, Serial No. 567,302, and in Germany October 9, 1930.

This invention relates to the production of artificial wool from vegetable fibre and to the artificial wool so produced.

My invention contemplates the conversion 5 of various kinds of vegetable fibre, prefer ably one belonging to the family of Tiliaceae, into a product closely resembling natural wool inappearance, texture, strength and other properties. I have found that jute, which is a member of the family of Tiliaceae, is best suited for such conversionsince it results in an artificial wool having most of the desirable properties of natural wool while having additional desirable propertles The various impregnating, washing and dehydrating steps of my improved process, by means of which the artificial Wool is produced, are preferably carried out in centrifuges which are preferably equipped with removable perforated or sieve baskets such as are well known; for supporting the fibre and permitting the ready removal thereof when desired. I have found that by the use of such centrifuges, a considerable saving of time may be effected, as well as reductions in the number of transfers of the material, and in the loss of fibre, and that it thereby becomes possible to draw off the greater part of the various chemicals used in the process, so that said chemicals may be recovered and used over again, whereby the process may be ca rried out commercially at minimum cost.

In accordance with my improved process, a

suitable vegetable fibre, for example, com- 'mercial or raw jute fibre, such as is obtained in the open market, is first cut into lengths of from ten to fifteen inches. This step is desirable because the fibre produced from such 40 lengths can easily be handled by the well known combing and carding machines customarily used in the manufacture of textile material. I

Should the jute fibre be left in its original lengths, the resultant wool produced therefromvcannot be efiiciently handled by such machines, due to the excessive force which would be required to perform the combing, carding and other operations thereon.

In order to separate the fibres from each other and into individual filaments, and to dissolve the gumsand other adhesive materials which hold the fibres together, and in order to destroy the ligtum contained in the ligneous fibres, the cut fibres are placed in a' centrifuge of the type above described containing a cold bath of caustic solution of high concentration. The solution preferably used is caustic soda at 30 Baum.

The fibre is left in the solution for approximately thirty minutes. This time is sufiicient to thoroughly separate the fibres into single filaments and to destroy the gums and ligtum contained in the jute, as well as to enable the thus separated filaments to curl or riod, the tensile strength of the resulting product is greatly decreased, as is also the case were a warm or hot solution used instead of a cold solution. I have also found that in the proportion stated, a period of thirty minutes completes the separation and cleansing of the fibres without the use of a too highly concentrated solution or the use of heat, since sufiicie'nt heat is developed during the reaction of the caustic soda upon the fibres. mum tensile strength is given to the individual filaments of the product, and maximum resiliency is imparted thereto during this step of the process, while the fibre is given a maximum and lasting shrinkage.

At the end of thirty minutes, the mass-of separated fibres is dehydrated in the same centrifuge, the soda solution being first run off and recovered.

After dehydration, the mass is removed mechanism, the mass being tumbled about I until the fibres are almost dry by rotating the tumbler continuously'in one direction, or rotating said tumbler first in one direction and then in the other, as may be found convenient or desirable. In this manner, the

I have also found that a maxiattack the fibre and make it brittle.

mass is quickly dried and excess of the liquid caustic soda solution is eliminated, thereby facilitating the treatment which follows. The heating of the mass may be obtained in the usual manner by means of steam pipes arranged adjacent the tumbler, the steam being at a temperature of from 212 to 250 F. The tumbling and reversing action serves to separate the filaments of the fibre to a considerable extent, said filaments becoming soft and resilient, and attaining the curl which is highly desirable in fibres intended to be later used for textile purposes. Furthermore, by drying the mass in a tumbler at a comparatively high temperature, uniform drying throughout the entire mass at a high rate of speed, usually about fifteen minutes, is attained. Other drying methods, even those involving the movement of the mass along heated conveyors or through heated chambers are comparatively inefficient in view of the fact that the interior of the mass usually remains wet in a manner not possible when the mass is tumbled, as above described, and said methods are further inefficient because of the failure thereof to produce the desired curl in the filaments.

lVhile the mass is still slightly moist and not yet completely dry, it is removed to a centrifuge for the next operation. I prefer to halt the drying operation before complete drying is obtained, as otherwise, due to the presence of a residue of caustic crystals, complete drying would permit such crystals to In the centrifuge, the mass is thoroughly washed with cold water in order to remove any caustic soda remaining therein. The washing is continued until the water which is run off is clear, and without indication of any ma terial amount of caustic soda therein, there- 'by facilitating the bleaching operation which follows. It will be understood that the alkali in the wash water may be recovered and reutilized.

The washing operation having been completed, the mass is then dehydrated to clean it and partially dry it preparatory to the performance of the bleaching operation which is the next step in the process.' Said bleaching operation is preferably performed in the same centrifuge in which the washing operation is carried out. The bleach which I prefer to use comprises a 5% solution of any suitable well known bleaching agenthaving an alkaline environment, such as for example, a solution including 15% of available chlorine, which may be in the form of sodium chloride or other bleaching powder, and 2% of caustic soda. The initial temperature of thebleaching bath may start at about 140 F. which may be increased to 160 F. as the operation progresses. I have found that about 20 to 25 minutes in the bleaching bath is sufficient to produce a good white fibre of maximum strength, the whiteness as well as the strength of the fibre depending upon the time during which the fibre is exposed to the bath. A longer immersion in the bath results in a whiter fibre, but of less strength. It will be understood that any well known textile bleaching agent in an alkaline environment, may be used to replace the particular bleachipg agent above specified and I therefore do not wish to be understood as limiting myself to the particular bleaching material mentioned.

After the mass has been bleached, the bleach is run off and may be re-used. The mass is then again washed with cold water and dehydrated in the same centrifuge in order to halt the bleaching action and to remove the odor thereof. By dehydrating the mass, it becomes possible to carry out the succeeding operation with ease, economy and accuracy. Said succeeding operation comprises the washin r of the mass in slightly acidulated water, pre erably a solution of hydrochloric acid, for the purpose of removing any of the caustic soda which may remain in the mass, it being understood that the washing operation mentioned may be carried out in the same centrifuge, the materials used be ing recovered for further use thereof.

After the neutralization of the mass, it is again washed with cold water in the same centrifuge in order to remove any trace, and to halt the effect, of the acid. The mass is then dehydrated to remove the excess water and to prepare it for maximum absorption of the material supplied in the next step of the process.

.pliability and resiliency, as well as the property of heat retention or insulation, differing little from that of natural wool. The impregnation of the mass with the fatty acid further serves to impart to the resulting artificial'wool the property of resisting the subsequent hard industrial treatment to which wool is subjected such as fullin and the like. The particular material whic I prefer to use is fatty acid made from unrefined wool grease, (lanolin) ,which has been sulphonated for neutralization, said fatt acid penetrating and being retained by the bres even after the finished wool has been subjected to the fulling and other operations customary in transforming it intocommercial textile material. The fibres absorb the fatty acid without difiiculty and thereby become pliable and of high tensile strength. As indicated, I prefor to use fatty acid which has been sulphonated in order to eliminate in so far as possible, the yellowish color imparted to most oil solutions, which tend to discolor the wool.

Finally, the excess of the fatty acid solution is drawn off, and the mass centrifuged for the same purpose. The mass is then dried in the drying tumbler heretofore mentioned at a temperature from 212 F. to 250 F until perfectly dry, which completes the process.

- ther be understood that the various baths and washes may be drawn off for the purpose of recovering the chemicals used therein for further utilization of said chemicals and consequent economy.

The product produced by the above process from jute, or similar raw vegetable fibre, is a white, resilient, long staple wool closely resembling natural wool in appearance, feel to the touch, textile adaptability, color, resiliency, softness and heat retaining or insulating properties.

My new artificial wooldifl'ers from cotton in that it has greater insulating properties than cotton, its filaments are of much greater length than those of long staple cotton, and possess greater resiliency because of the curl produced in the fibres by the various operations above described.

My new wool can be spun without admixture with other materials and produces a good felt or yarn. If desired, however, it can be mixed in any desired proportions with natural wool, cotton, natural silk, or artificial silk, or other textile fibres and their wastes. Tests have shown that the insulating or heat producing properties of my new wool is about 90% of that of natural wool, but that the filaments of my new wool have a tensile strength about 2 times that of natural wool, and therefore it withstands mechanical treatment far better than such treatment is withstood by natural wool. Y

My new product may be combed, carded, and turned into yarn or felt by precisely the same machinery now used for the same purposes in connection with natural wool, no special machinery being required for this pur pose in View of the high tensile strength of mynew product, the resiliency thereof, and the comparatively great length of the filaments thereof when out as indicated in the first step of my new process above described.

No special dyes are necessary to color my new product since. it can be dyed by the same materials and in the same manner as all vegetable fibres are dyed. The product has numerous uses such as for example, in the manufacture into yarn mixed with carded wool; or its mixture with wool for felting, or mixing with natural wool for textile fabrics of all kinds, and mixing with short fibres; or mixing with wool for very fine carded blanket material; or mixing with natural wool to be combed and turned into worsted yarn.

In the above description of my new process, I have statedcertain specific proportions, ingredients, temperatures and times of operation, but it will be understood that I do not desire to limit myself specificially thereto except in so far as I have indicated, since it will be understood that various changes may be made therein and various equivalent ingredients substituted, and I therefore do not intend to limit my invention thereto, but intend to claim my invention as broadly as may be permitted by the state of the prior art and the scope of the appended claims.

I claim:

1. The method of treating vegetable fibres to convert said fibres into material resem bling natural wool in quality and in appearance, consisting of treating the cut fibres with an alka i solution until substances holding the fibres together are dissolved and the individual fibres become separated, and thereafter drying the fibres until they begin to crinkle, bleaching the fibres, neutralizing the alkali therein, impregnating the fibres with'a fatty acid made from wool grease and then again drying the fibres in a heated tumbler.

2. The method of treating vegetable fibres of the Tilaceae family such as jute, to convert said fibres into material resembling natural wool in quality and in appearance, consisting of treating a mass of fibres with -a cod caustic soda solution of 30 Baum for about thirty minutes, dehydrating the mass, drying the mass in a heated tumbler until almost dry, washing the mass with cold water, dehydrating the washed mass, treating the mass with a bleaching solution in an alkaline environment, again washing and dehydrating the mass, then treating the mass with a water solution of 5% of hydrochloric acid, again washing and dehydrating the mass, immersing the mass in a bath of sulphonated fatty acid, removing the excess fatty acid and finally drying in a heated tumbler while agitating and changing the positions of the parts of the mass.

3. The method of treating vegetable fibres of the Tilaceae family such as jute, to convert said fibres into material resembling natural wool in quality and in appearance, consisting of removing the material holding the fibres together by treating the fibres with a cold caustic solution for about thirty minutes, removing the surplus solution, drying the mass in a heated rotary tumbler until the moving the excess fatty acid and finally,

again drying the mass in a heated rotary tumbler, all the steps excepting the drying steps being carried "out in a rotary centrifuge equipped with a perforated basket whereby the materials used in the various steps are recovered.

4. The method of treating vegetable fibres to convert said fibres into artificial wool consisting of subjecting the fibres to a bath adapted to remove the material holding the individual fibres together to separate said fibres, then drying the fibres in a heated rotary tumbler to impart a curl and resiliency to the fibres, bleaching the fibres, impregnating them with a sulphonated fatty acid and again drying thefibres in a heated rotary tumbler.

5. The method of treating vegetable fibres,

including removing therefrom by'a bath, the

ligneous material and similar substances which keep the fibres united, then drying the fibres by dry heat and agitation.

6. The method of treating vegetable fibres, including as an intermediate step and as a final step, the drying of said fibres by dry heat and agitation.

7. The method of treating vegetable fibres including impregnating said fibres with a fatty acid made from wool grease and drying the impregnated fibres in a heated tumbler.

8. The method of treating vegetable fibres comprising the removal of the vegetable gums, ligneous material and other substances which keep the fibres "united, by means of a caustic solution, drying the fibres in a heated tumbler until they are almost but not quite dry, bleaching the fibres in an alkaline environment, neutralizing the alkali therein, impregnating the fibres with a fatty acid and finally, again drying the fibres in a heated tumbler.

9. The method of treating vegetable fibres including cutting the fibres to lengths not exceeding fifteen inches and treating the cut fibres in a centrifuge with a caustic solution of 30 Baum for about thirty minutes, and then drying the fibres in a heated tumbling machine.

10. The method of treating vegetable fibres including as an intermediate step, drying the fibres in a heated rotary tumbler and as final steps, impregnating the fibres with a fatty acid made from wool grease and then again drying the fibres in a heated rotary tumbler.

11. The method of treating vegetable fibres comprisingimmersing the fibres in a strong cold caustic solution for about thirty minutes, bleaching the fibres in an alkaline environment neutralizin the effect of the alkali, impregnating the bres with a sulphonated fatty acid, washing the fibres with cold water and dehydrating them between each of the above-mentioned steps in a centrifuge and drying the fibres in a heated tumbler after the treatment with the caustic solution and again as the final step of the process.

12. An artificial wool comprising vegetable fibres from which the vegetable gums and ligtum have been removed and which has been bleached said wool being impregnated in its finished state with a sulphonated fatty acid, the fibres of said artificial wool having most of the characteristics of natural wool and being of greater tensile strengththan natural wool and longer and more resilient than cotton fibres.

13. An artificial wool comprising vegetable fibre impregnated with a fatty acid made from wool grease and composed of long, curly fibres having the characteristics of natural wool.

14. An artificial wool comprising vegetable fibre impregnated with a sulphonated fatty acid made from wool grease.

15. An artificial wool having long, curly and resilient fibres and having the color, heat-retaining properties, softness to the touch, and at least as much tensile strength as natural wool, and adapted to be combed, carded, and made into yarn by the same machinery as that used for natural wool.

16. A long, staple, artificial wool of vegetable fibres from which the vegetable gums, ligneous material and similar substances which keep the fibres united, have been removed, and which has been bleached, impregnated with a. sulphonated fatty acid and dried until the fibres become curly, the fibres of said artificial wool having a greater tensile strength than those of natural wool and only slightly less heat-retaining properties than those of natural wool and otherwise closely resembling and having many of the properties of natural wool.

17. An artificial wool formed of jute fibres cut to lengths of ten to fifteen inches and treated with a caustic solution, washed,

dried, bleached and impregnated with sulphonated fatty acid made from wool grease wherein the fibres are longer than those of long staple cotton wherein the fibres have a tensile strength greater than that of natural wool fibres, and having about 90% of the heat retaining properties and curl of natural wool, said artificial wool being adapted to be fulled, carded, combed and spun by the same processes and the same machinery used for the same purposes for natural wool, and said artificial wool being adapted to be dyed in the same manner and with the same dyes as othervegetable fibres, and being further adapted to be mixed with natural wool, cotton, and natural and artificial silk, and other 7 textile fibres.

GINO M. ROSSATI. 

